Patent · US Expired

Variable speed control for a brushless direct current motor

US4603283A · kind A · utility

30Cited by
11References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 3, 1985
Grant dateJul 29, 1986
Priority date
Expiry dateJun 3, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P6/182
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A variable speed control for an encoderless, brushless, direct current motor. An input signal, representing a desired speed of the motor, is received by both a variable power supply and a counter. The counter responsively issues a sequence of signals corresponding to particular motor windings to be energized. The variable power supply issues a motor supply voltage in accordance with the input signal as well. An error corrector circuit is connected to both the counter and the windings of the motor. The corrector circuit senses a voltage waveform on a winding when the counter signal indicates that the winding is not energized. If the winding voltage waveform deviates from a predetermined standard, the corrector circuit gives a correction command to the variable power supply. The variable power supply accordingly increases or decreases the motor supply voltage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.